Jim, Standard EN 61000-4-2, March 1995 Section 8.3.1 is specific in prescribing ESD application "to such points and surfaces of the EUT which are accessible to personnel during normal usage". Standard does not distinguish front from rear panel.
You could justify to test front panel only, if the EUT is installed in a cabinet with the rear panel not accessible to personnel during normal usage including customer's maintenance. Ports should be terminated with cables during ESD testing. I/O circuits could be designed to withstand direct ESD hits, typically with two components per signal one to limit input current, the other to clamp penetrated voltage. Good Luck, Mirko Matejic ---------- From: Jim To To: Matejic, Mirko Cc: 'treg' Subject: Re: BOUNCE [email protected]: Non-member submission from [Jim To <[email protected]>] (fwd) List-Post: [email protected] Date: Wednesday, July 22, 1998 10:48AM Thank you for your comments. It appears that the standard does not specify the application of ESD to the rear I/O ports of a unit. However, if there are front I/O ports, then ESD is required on the exposed metal parts. I/O ports provided at the front panel do not always get connected to interconnecting cables. Would you have to consider a worse scenario by assuming that cables are not connected? Has anyone have the experience, good or bad, on conducting ESD directly to the exposed pins of I/O ports? Many thanks. Jim To Force Computers, Inc. Matejic, Mirko wrote: > Jim, > > All user accessible areas should be tested to ESD immunity. > > However, with test setup having RS232 connector terminated > with a cable, I/O connector pins would not be accessible. RS232 > connector shell will be accessible and should be tested as such. > > Mirko Matejic >
